(Reuters) - West Ham United defender Carl Jenkinson suffered a "significant injury" to his left knee during their 2-2 Premier League draw with Manchester City, the club said on Tuesday.

The 23-year-old, who is on loan at West Ham from Arsenal and has made 23 appearances for the Hammers in all competitions this season, sustained the injury when he conceded a penalty for a tackle on Sergio Aguero during Saturday's match.

"Unfortunately, it appears that Carl has suffered a significant injury and he will be assessed by a specialist in central London on Wednesday," West Ham said in a statement on their website (www.whufc.com).

Jack Sullivan, son of West Ham's co-chairman David Sullivan, said on Twitter that the injury would rule Jenkinson out for the season.

"Carl Jenkinson's injury is far more serious than we thought," he said.